Security Digest · Vulnerability record
CVE-2025-58367: DeepDiff Class Pollution in Delta class leading to DoS, Remote Code Execution, and more
DeepDiff is a project focused on Deep Difference and search of any Python data.
CVSS 10.0 Critical EPSS 1.2% · p68
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 1.2%, percentile 68: FIRST’s model estimates a 1.2% chance of exploitation activity in the next 30 days, higher than 68% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
deepdiff(PyPI) >= 5.0.0, <= 8.6.0, fixed in 8.6.1. Check your lockfile, including transitive dependencies.
What it is
DeepDiff is a project focused on Deep Difference and search of any Python data. Versions 5.0.0 through 8.6.0 are vulnerable to class pollution via the Delta class constructor, and when combined with a gadget available in DeltaDiff, it can lead to Denial of Service and Remote Code Execution (via insecure Pickle deserialization) exploitation. The gadget available in DeepDiff allows deepdiff.serialization.SAFETOIMPORT to be modified to allow dangerous classes such as posix.system, and then perform insecure Pickle deserialization via the Delta class. This potentially allows any Python code to be executed, given that the input to Delta is user-controlled. Depending on the application where DeepDiff is used, this can also lead to other vulnerabilities. This is fixed in version 8.6.1.
From the GitHub advisory
Summary Python class pollution is a novel vulnerability categorized under CWE-915. The Delta class is vulnerable to class pollution via its constructor, and when combined with a gadget available in DeltaDiff itself, it can lead to Denial of Service and Remote Code Execution (via insecure Pickle deserialization).
The gadget available in DeepDiff allows deepdiff.serialization.SAFETOIMPORT to be modified to allow dangerous classes such as posix.system, and then perform insecure Pickle deserialization via the Delta class. This potentially allows any Python code to be executed, given that the input to Delta is user-controlled.
Depending on the application where DeepDiff is used, this can also lead to other vulnerabilities. For example, in a web application, it might be possible to bypass authentication via class pollution.
Details
The Delta class can take different object types as a parameter in its constructor, such as a DeltaDiff object, a dictionary, or even just bytes (that are deserialized via Pickle).
Weakness type: CWE-915.
Product: deepdiff (PyPI) · Assigned by: GitHub_M · Published: 2025-09-05
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| PyPI | deepdiff | >= 5.0.0, <= 8.6.0 | 8.6.1 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| seperman | deepdiff | >= 5.0.0, < 8.6.1 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 4.0 | 10 Critical | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
| GitHub | 4.0 | 10.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Attack requirements: none
- Privileges required: none (no login)
- User interaction: none
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc, automatable no, technical impact partial.
- FIRST EPSS (model of 2026-10-21): 1.19% probability of exploitation activity in the next 30 days; percentile 68.
Timeline
- — GitHub-reviewed advisory GHSA-mw26-5g2v-hqw3 published (critical)
- — CVE record published by GitHub_M
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-mw26-5g2v-hqw3 github.com
- CVE.org record CVE-2025-58367 cve.org
- NVD entry CVE-2025-58367 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com
- github.com github.com